5 Answers
5

This is to infuse the cooking oil with these flavours. Cook for short amount of time ~30secs.

onions/peppers/carrots/harder veg

These need a little more cooking that the other bits, so I give them a bit longer.

mushrooms/sugar snaps/soft veg

These need less cooking, so bit less time.

bean sprouts

I like these to be a bit crunchy so add them right at then end and basically just warm through.

If I'm using bigger veg like broccoli/cauliflower then I do them separately to the other veg. I use a little of the chili/garlic/ginger and fry that for 30 secs, add the broccoli fry for another minute or so just to brown the florets, then add some water, turn down the heat and put on a lid, to steam the broccoli. Once its done I remove to a separate plate the add back in at the end.

It basically depends on how much you like each veg cooked. If you prefer your peppers crunchy, put them in nearer the end.

An answer below mentioned meats. When I do it, I fry the meat to get a good sear and cook it about 75% done. Then I set it aside and do the vegetables in the general order presented by Sam. I then add the meat back as I add the last vegetables, cook for a minute or two to heat everything up and incorporate the flavors into the meat, then add the sauce. Stir to coat/thicken, and you are done.
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JSMMay 28 '14 at 20:22

All the advice above is good, but let me add one more thing to consider: if you don't have a wok burner with the power of a fighter jet, you might want to not cook everything together at all. It often is best to cook one or two ingredients at a time, in a thin layer over the highest possible heat, until they are 20 seconds short of done, and then remove them to a bowl temporarily. When the last ingredient is just about cooked, add everything else back and then add the sauce, stir a couple of times to get everything back up to temperature and serve.

The general rule is to put in aromatics first--stuff that contributes good smells. Traditionally that includes garlic, onions, dried spices, and celery. In oil,of course.

Then the hard to soft rule applies. The general idea is to have all of the food 'ready' at the same time, despite differences in cooking time. So you give the harder items, i.e. carrots, longer. More cooking time is required for items which have starches which need to be broken down (potatoes, carrots) or a fibrous structure that needs to be broken down (broccoli).

Proteins are a separate category and it depends on the amount of connective tissue (cubed beef, more time) or delicacy (lobster, less time). Either way, you don't want to overcook meats. Last, add ingredients that you really don't want to overcook, like fresh herbs, bean sprouts, lighter greens, lemon juice.

There is absolutely a better way than just adding everything together. But it depends, in part, upon your tastes.

I like my mushrooms very well done, so I will toss the mushrooms and onions in together first. Sugar snaps, bell peppers and bean sprouts I like nice and crisp, so I'll toss them in last just to heat them up. For just a minute or so. The jalapenos can go in any time depending on how much you want their spice to absorb into the oil. The earlier they go in, the spicier the whole affair will be. With other ingredients they may need to go in earlier or later depending on how much they need to cook and how well done you like them. For example, things like carrots, broccoli or cauliflower may need to be blanched before they go in, or go in much earlier than other things. Spices such as garlic or ginger should go in first or very early so they have plenty of time to infuse into the oil.

It really comes down to the ingredients and your tastes. Try adding things in different orders and letting them cook for different amounts of time to see what you really like.